Case 2, presented by S. Robert Rozbruch, MD describes a 9-year-old male who presented to HSS with a 5.5cm Leg Length Discrepancy (LLD) (Figure 1). There was no history of infection or trauma and growth plates looked normal on x-ray. This appeared to be a congenital LLD and the predicted LLD at maturity was thought to be 7.5cm using standard prediction methods. He underwent a right femur lengthening of 5cm using a monolateral frame on the femur (Figure 2). A minimal incision quadricepsplasty was done to treat a knee extension contracture. This was uneventful and it was planned to do another small lengthening as a young teenager. However, during follow up, the growth plates were noted to be increasingly irregular. At ages 12 and 15 years, the patient was noted to have additional LLD requiring further staged lengthening. In total, he underwent 20cm of right lower extremity lengthening in 3 stages (Figures 5, 6). The patient is now 21 years of age and has equal leg lengths, a normal gait, and normal hip, knee, and ankle range of motion. He has no functional limitations.